Just like I don’t rely on Facebook to store my family pics in perpetuity, I definitely don’t rely on iNaturalist for photo storage. They’re compressed versions anyway. People should be using other cloud and physical back-ups for photo storage.
FWIW, similar questions have been asked and responded to by staff in the past, e.g. here’s what Scott said in August 2017 (which, as such, may now be outdated):
@loarie: iNat’s assets are currently stored on Amazon Web Service, and the database is stored at Rackspace, we have backups at Datapipe.
iNat is owned by the California Academy of Sciences a museum that has been responsible for maintaining one of the world’s largest natural history collections for over 100 years. iNaturalist has been online since 2008 and we certainly expect to be around for another 10 years. The iNat program is a ‘core’ part of the Museum budget (ie not soft money) but I’d be lying if I said program-focus in the non-profit world isn’t volatile. However, we have 3 years of funding ‘in hand’ which is about as good as anyone can expect in the non-profit world. Furthermore, much of our past, current, and future work is to ensure the long term sustainability of iNat through fund-raising and partnerships.
And, as of June 2017 iNat is “jointly supported” by CAS and National Geographic Society. There is also a handy donate button at the bottom of each page on the website and apps settings pages. ;)